1. Field of the Invention
The present invention relates to a collapsible telescopic steering apparatus adapted to reduce shock during vehicle collision.
2. Description of Related Arts
One type of collapsible steering apparatus has an arrangement wherein a pair of tubes of a steering column are press-fitted with each other so as to be slidably movable relative to each other during collision for absorption of the shock of the collision.
On the other hand, there is proposed a mechanism which accomplishes a telescopic adjustment function based on the above pair of tubes adapted for relative sliding movement for shock absorption, the telescopic adjustment function permitting the positional adjustment of a steering wheel with respect to the axial direction of the tubes. In one exemplary arrangement, an outer tube is formed with a slit at a fitting portion thereof so that the outer tube can releasably clamp an inner tube. The outer tube establishes a press-fit state by clamping the inner tube. On the other hand, the outer tube establishes a loose-fit state by unclamping the inner tube thereby permitting the telescopic adjustment.
In order to permit the telescopic adjustment, however, the outer tube cannot clamp the inner tube with such a great force. Hence, the definition of shock absorption load at vehicle collision is decreased in the degree of freedom.